Diki,

Sorry to hear of your malady. The last thing a keyboard player needs is hand problems--I should know. The only thing I know that works for trigger finger is a regiment of steroids, usually Prednisone, which can have some nasty side effects, plus splinting, which allows the tendon to heal naturally. The combination usually takes a month or more to work, but the bottom line is trigger finger is essentially a warning that you may have to lighten your left hand playing technique. It's usually the result of tendon inflammation due to some sort of repetitive process.

Good luck,

Gary